Level 1 PSLE
Cody packed 596 buttons into four cartons, labelled A, B, C and D. Carton A had the most number of buttons and Carton D had the least. The difference in the number of buttons between Carton A and the number of buttons in the other three cartons were 12, 36 and 64 respectively. How many buttons were there in Carton D?
Level 2 PSLE
Two numbers add up to 425. If one of them is a 2-digit number and the other is a 3-digit number, what is the largest possible difference between the two numbers?